Obs. rare–1. In 5 summe. [Echoic. Cf. late MHG., G. summen, NFris. summi; also BUM v.2, HUM v.1] intr. To hum softly.
c. 1440. Pallad. on Husb., VII. 123. Al subtilly and smale yf that they summe, Al hugely and haske yf that they humme.
